Spring lathe-tool



I. PAL.

SPRING LATHE TOOL. APPLICATION mgn MAR. 12. I920.

1,354,77 Patented Oct. 5,1920.

9 F g-Z. 8 H1 .5. 111

INVENTQR. [Shara Pal 7 ATTORNEY.

UNITED STATES IsrvAN PAL, or CLEVELAND, 01110.

SPRING- LATHE-TOOL.

Specification of Letters Patent.

Patented Oct. 5,1920.

Application filed March 12, 1920. Serial No. 365,136.

To all whom it may concern:

Be it known that I, Is'rvAN PAL, citizen of Hungary and resident of Cleveland, in the county of Cuyahoga and State of Ohio, have invented certain new and useful Improvements in Spring Lathe-Tools, of which the following is a specification.

This invention relates to lathe tool holders, and has for. its object the provision of a spring lathe tool holder designed to allow slight movement of the cutting edge of .the tool in the direction of the axis of the work and in a direction perpendicular to said axis'when abnormal pressure is put upon the tool during the cutting operation.

To attain the above and other objects, I employ the arrangement and combination of parts shown in their preferred forms in the accompanying drawings, in which,

Figure l is a front view and partial vertical section of'my invention, showing a thread cutting tool supported in my 1mproved holder. Fig. 2 is a plan view of the same. Fig.3 is a horizontal section on line 25.

3-3 of Fig. 1.

My improved device is especially advantageous when used in connection with a thread cutting tool as 1. The body member 2 of the tool holder is made of the usual shape and size to fit into and to be supported in the tool post of a lathe, a portion 3 of circular cross section, bent into the form of an inverted -U commonly known as a ooseneck bein inserted into and assg mg through a suitable hole in the end of said member 2.

A collar4 on said bent portion prevents downward motion of said bend relatively to said body ember 2, and a head 5 suitably formed in any well known manner at the lower end of said bent portion after it has been inserted into member 2, acts to prevent upward motion of said bent portion xrelatively to saidfinember, though it will be understood that, if no means are used to prevent it, the entire bent portion may be made to rotate to some extent about the axis of the hole through which said bent portion is inserted.

The unattached part of said bent portion 3 terminates in a rectangular prismatic portion 6 having a suitable opening therein for receiving a tool as '1. A set screw 7 is suitably arranged in said portion 6 to prevent movement of said tool therein, and a heavy spring 8 is inserted between member 2 and extremity 6, said spring tending to urge the twolast mentioned portions of the holder apart and to resist rotative movement of said bent portion 3.

After a first out has been made in the work 9 whereby the cutting of the thread is commenced, it is often difiicult to get the succeeding cuts to follow the first exactly. Slight inaccuracies in the registration of the new cut with the previous one are taken up by my improved holder, which adjusts itself to make a cut offering the least resistance to the tool, this being effectuated by the tendency of the forward part of bent portion 3 to rotate about the other end against the action of springs 8, when any abnormal force is applied to the tool.

Spring 8 is made of suflicient strength to hold tool 1 normally in'line with member 2. For accurate Work Where differences in the hardness of the stock operated on would cause chattering of the tool and uneven work, or would cause the tool, if held in the ordinary tool holder, to break, my improved tool holder has sufficient give to carry the tool past the bad spot gradually, due to the gooseneck or bent portion 3 and to the fact that said bent portion is rotatable to some extent as above described.

What I claim is:

1. In a tool holder, a body member for insertion in the tool post of a'lathe, rotatable tool holding means mounted in said body member, and a spring for holding said rotatable means normally in line with said body member.

2. In a tool holder, a body member for insertion in the tool post of a lathe, a part having a 180 bend rotatably mounted at one end thereof in said body member, a set screw for holding a tool in the other end of said bend, and a spring inserted between the end of said body member and the toolholding end of said bend for holding said rotatable bend normally in line with said body member..

Signed at' Cleveland, in the Cu ahoga and State of Ohio, of arch, A. D. 1920.

county of this 8th day ISTVAN PAL. 

